Harry March's troubles begin when Lapham, a self-aggrandizing, ostentatious multimillionaire, commences construction of a 36,000-square-foot house (complete with a cutting-edge air-conditioner that cools his entire eight-acre property) directly across the creek from Harry's island home in Quogue, in the Hamptons. Harry, an island himself, is something of a wreck and half-nuts, but principled. His wife has left him for an event planner in Beverly Hills; he cuts the polo player out of his shirts; and he speaks mainly with his dog, Hector, a born-again Evangelical and a capitalist who admires Lapham's monstrosity as a symbol of American progress. But to Harry, Lapham represents everything that is ruining modern civilization. So he sends daily notes to his nemesis by way of a remote-control toy motorboat, which read: "Mr. Lapham, tear down that house!" When his efforts fail, he turns to politics by other means.]

Lapham Rising follows Harry's progress during a single day -- through the strange habits of Hamptons social life; the power of local real estate (embodied in Kathy Polite, who advertises her agency by swimming naked from her boat every morning); the odd workings of his own mind, such as it is; and into his elaborate plot to devise a weapon of individual destruction with which to bring down Lapham and all the Laphams of the world. Of course, it backfires.

An eccentric writer living as a recluse on his own island with his talking dog Hector comes up with a scheme to take on his irritating new neighbor, a multimillionaire named Lapham who is building a grotesquely enormous new home next door.